moved sleep function to lib.rs

V2/sleep/src/lib.rs

@@ -0,0 +1,42 @@
+extern crate libc;
+
+use std::time::Duration;
+use libc::{c_int, c_long, time_t, timespec};
+
+const CLOCK_MONOTONIC: i32 = 1;
+
+#[cfg(target_os = "linux")]
+fn clock_nanosleep(clk_id: libc::clockid_t, flags: libc::c_int, rqtp: *const libc::timespec, rmtp: *mut libc::timespec) -> libc::c_int {
+    unsafe { libc::clock_nanosleep(clk_id, flags, rqtp as *const _, rmtp as *mut _) }
+}
+
+#[cfg(target_os = "macos")]
+fn clock_nanosleep(_clk_id: libc::c_int, _flags: libc::c_int, rqtp: *const libc::timespec, rmtp: *mut libc::timespec) -> libc::c_int {
+    unsafe { libc::nanosleep(rqtp as *const _, rmtp as *mut _) }
+}
+
+pub fn sleep(duration: Duration) -> Result<Duration, c_int> {
+    let ts = duration_to_timespec(duration);
+    let mut remain = timespec {
+        tv_sec: 0,
+        tv_nsec: 0,
+    };
+    let ret = clock_nanosleep(CLOCK_MONOTONIC, 0, &ts, &mut remain);
+
+    if ret == 0 {
+        Ok(timespec_to_duration(remain))
+    } else {
+        Err(ret)
+    }
+}
+
+fn duration_to_timespec(duration: Duration) -> timespec {
+    timespec {
+        tv_sec: duration.as_secs() as time_t,
+        tv_nsec: duration.subsec_nanos() as c_long,
+    }
+}
+
+fn timespec_to_duration(timespec: timespec) -> Duration {
+    Duration::new(timespec.tv_sec as u64, timespec.tv_nsec as u32)
+}